Following the demolition works undertaken at 79 Camden Road, Erith were appointed to undertake the basement works.
Whilst sheet piling and bearing piles were installed the basement reconstruction works commenced.
The sites footprint spanned 3744m2. The excavation depth, from the ground level to create the single storey basement, was 3.5m from the original ground level to the underside of the lower basement slab.The works involved installing sheet piles to the site perimeter with circa 600 bearing piles within the site. 13,400m3 volume of excavated material was removed from site with the piling mat removal and arisings adding to the overall material for off-site disposal.
Due to the basement being a habitable floor area it was necessary to ensure it remained waterproof. Grade 3 waterproofing was achieved by using a combination of Cetco voltex membrane with Pudlo Waterproof Concrete. This was a Contractors Design Proportion (CDP) that Erith developed using two separate systems with warranties for both handed over as part of the O&M documentation.
2 tower cranes were installed in advance of the main excavation and reconstructions works. This commenced by carrying out a local excavation and breaking down of bearing piles within a temporary works constructed from sheet piles. In addition, pile caps were installed as well as drainage, ducts, and district heating pipework within the lower ground floor stab together with attenuation tanks, pumps and rising mains for both the foul and the storm water systems.
The lower ground floor slab was constructed with a Cetco
membrane and Pudlo waterproof concrete. Further to this, vertical
elements were installed including; colums, lift and stair cores and one sided walls in front of the perimeter sheet piling. Following this the ground floor was then constructed.
As the works progressed across the site, areas of the ground floor slab were handed over to company undertaking the super structure works to start the above the ground floor slab whilst Erith remained Principle Contractor.
Furthermore, throughout the duration of the 40 week contract, real time noise, dust and vibrating monitoring took place with the trigger level having been defined by Camden Council. As the site was encompassed by conservation areas it was imperative to keep all disturbance levels to a minimum.